Cold end optimization algorithm of steam turbine

The invention provides a cold end optimization algorithm of a steam turbine. The method comprises the following steps: S1, determining a power ratio K1 value; s2, determining a function relational expression of circulating water temperature rise and a to-be-fitted formula K2; s3, determining the saturated back pressure Pa of the steam turbine and/or determining the current steam exhaust temperature T1; s4, supposing that the current of the circulating pump is slightly increased by A, determining a circulating water temperature rise variable T or an exhaust steam temperature T3 after the circulating pump is slightly increased; s5, determining the backpressure Pb of the steam turbine after the current of the circulating pump is slightly increased; s6, empirical consumption difference analysis data K3 are obtained, and the coal saving amount M1 is calculated according to the back pressure drop amplitude of the steam turbine; and S7, judging whether to increase the output of the circulating pump according to the